Yamaha YZ450FX 2019 Owner's Service Manual page 309

SIGNALING SYSTEM
4. Joint connector
5. Main relay
7. Battery
8. Frame ground
9. Main fuse
15.Warning light
16.Fuel level warning light
18.Resistor
19.Fuel sender
21.ECU (Engine Control Unit)
A. Battery sub-lead
B. Wire harness
8-14